"We're looking for a bit of a rebound in global growth in the second half, in the U.S. and also in China, where we do expect a stabilisation, and this should provide some upside to metals prices. Positioning has turned quite bearish, a lot of negative news is already priced in the market."
Three-month copper on the London Metal Exchange failed to trade in official open outcry activity and was bid down 0.5% at $5,846 a tonne, moving back towards a five-month low of $5,740 touched on Monday.
But LME aluminium added 0.4% to trade at $1,785 in official rings, heading away from a 29-month nadir reached on Monday.
* ALUMINIUM PREMIUM: Some Japanese aluminium buyers have agreed to pay a premium of $108 per tonne for shipments in July to September, up 3% from the current quarter, amid tighter supply in Asia, sources said on Wednesday.
* TRADE TALKS: Sentiment has been hit by worries about expected talks between the Chinese and U.S. leaders later this month after sources told Reuters there has been little preparation for a meeting and expectations were low for progress at ending the trade war.
"All of these trade talk uncertainties have put base metals or commodities space into hostage. If this overarching issue is not removed or diminished, there's no way for base metals to have any meaningful direction," said analyst Helen Lau at Argonaut Securities.
* COPPER SMELTER: Zambia's Konkola Copper Mines, owned by Vedanta Resources , plans to restart its Nchanga smelter on June 22 , the company said on Wednesday.
* LEAD SPREAD: The premium of cash LME lead over the three-month contract remained relatively strong at $33.50 a tonne at Tuesday's close, down from $42.50 touched a day earlier, the highest since January 2017 and indicating shortages of available supplies.
* PRICES: LME nickel was bid down 0.5% to $11,825 a tonne in official rings, zinc gained 0.2% to trade at $2,512, lead shed 1.6% to trade at $1,883 and tin was bid 0.6% lower at $19,050.
(Additional reporting by Mai Nguyen in Singapore. Editing by Jane Merriman and Louise Heavens) ((firstname.lastname@example.org; +44 20 7542 7093; Twitter https://twitter.com/reutersEricO; Reuters Messaging: email@example.com))